1. Field of Invention
The present invention relates to the design construction of optical devices. The present invention is more particularly related to the use of internal frames in the design and construction of optical devices. The present invention is yet further related to the use of frames in the design and construction of Liquid Crystal On Silicon (LCOS) kernels.
2. Discussion of Background
The components of an LCOS based video projector 100 are explained by example of a light engine with reference to FIG. 1. As shown, white light 110 is generated by a light source 105. The light is collected, homogenized, polarized, and formed into the proper shape and otherwise processed by optics (not all shown for clarity). The light then enters a prism assembly 150 where it is broken into red, green and blue polarized light beams. A set of reflective microdisplays 152A, 152B, and 152C are provided and positioned to correspond to each of the polarized light beams (the prism assembly 150 with the attached microdisplays is called a kernel). The beams then follow different paths within the prism assembly 150 such that each beam is directed to a specific reflective microdisplay. The microdisplay that interacts with (reflects) the green beam modulates the green content of a full color video image. Similarly, the red and blue contents of the full color image are modulated by corresponding “red” and “blue” microdisplays. The prism assembly 150 then recombines the modulated beams into a modulated white light beam 160 that contains the full color video image. The resultant modulated white light beam 160 then exits the prism assembly 150 and enters a projection lens 165. Finally, the image-containing beam (white light beam 160 has been modulated and now contains the full color image) is projected onto a screen 170.
The kernel is constructed, for example, from a set of beam splitters. The example kernel in FIG. 1 uses a set of 4 polarizing beam splitters. Depending on the design of the kernel, other optical components (e.g., mainly optical elements such as polarizers, waveplates, Color Selects, filters, dichroics, optical blanks, etc.) may be disposed at various locations within the kernel. In the example kernel of FIG. 1, certain optical elements are disposed, for example, between adjacent faces of the beamsplitters.